# Copyright 2016, Tresys Technology, LLC # # SPDX-License-Identifier: LGPL-2.1-only # from typing import NamedTuple, Optional from ..policyrep import Default, DefaultRuletype, DefaultValue, DefaultRangeValue, ObjClass from .descriptors import DiffResultDescriptor from .difference import Difference, SymbolWrapper, Wrapper class ModifiedDefault(NamedTuple): """Difference details for a modified default_*.""" rule: Default added_default: Optional[DefaultValue] removed_default: Optional[DefaultValue] added_default_range: Optional[DefaultRangeValue] removed_default_range: Optional[DefaultRangeValue] class DefaultsDifference(Difference): """Determine the difference in default_* between two policies.""" added_defaults = DiffResultDescriptor("diff_defaults") removed_defaults = DiffResultDescriptor("diff_defaults") modified_defaults = DiffResultDescriptor("diff_defaults") def diff_defaults(self) -> None: """Generate the difference in type defaults between the policies.""" self.log.info( "Generating default_* differences from {0.left_policy} to {0.right_policy}". format(self)) self.added_defaults, self.removed_defaults, matched_defaults = self._set_diff( (DefaultWrapper(d) for d in self.left_policy.defaults()), (DefaultWrapper(d) for d in self.right_policy.defaults())) self.modified_defaults = [] for left_default, right_default in matched_defaults: # Criteria for modified defaults # 1. change to default setting # 2. change to default range if left_default.default != right_default.default: removed_default = left_default.default added_default = right_default.default else: removed_default = None added_default = None try: if left_default.default_range != right_default.default_range: removed_default_range = left_default.default_range added_default_range = right_default.default_range else: removed_default_range = None added_default_range = None except AttributeError: removed_default_range = None added_default_range = None if removed_default or removed_default_range: self.modified_defaults.append( ModifiedDefault(left_default, added_default, removed_default, added_default_range, removed_default_range)) # # Internal functions # def _reset_diff(self) -> None: """Reset diff results on policy changes.""" self.log.debug("Resetting default_* differences") self.added_defaults = None self.removed_defaults = None self.modified_defaults = None class DefaultWrapper(Wrapper[Default]): """Wrap default_* to allow comparisons.""" __slots__ = ("ruletype", "tclass") def __init__(self, default: Default) -> None: self.origin = default self.ruletype = default.ruletype self.tclass = SymbolWrapper(default.tclass) self.key = hash(default) def __hash__(self): return self.key def __lt__(self, other): return self.key < other.key def __eq__(self, other): return self.ruletype == other.ruletype and \ self.tclass == other.tclass